Because it is the truth and logical. I have been cutting out crosses for years (mounted on the 6pt stringing machine) and replace with new. Never had a single crack. Its totally safe IMO.
-something to consider
-i like to think of it as "pulling pressure applied", and why good practices should be observed
-as a stringer, you have to go through trials and errors to see what happens, IMO
-I've warped, ballooned, played and felt the differences when different pressures are applied
-on a standard 6pt mounting machine
-only the 2 12/6 oclock posts are preventing racquet from collapsing/flexing inwards, holding the mains-pressure back
-the other 4 posts (2/4/8/10) are holding the racquet from ballooning-out/flexing outwards, from the pressure from the mains
-when the pressure from the mains is gone (dead poly for example, on a poly.mains/multi.cross scenario) and you just replace the crosses, you are pulling with pressure "inwards", with
nothing to push-back/counter
-furthermore, on "most" racquet, there are usually 19 cross strings pulling, more than just # of the mains, and thusly why pressure and counter pressure should be observed and applied with "understanding"
-btw, i know people who do and have done this
-ive also done this myself, (as ive said above) to experiment,
-imo a stringer should try any and all, to know what he/she is talking about and advising people by trying it themselves first
-when its their racquet, no problem, do as you wish
-if you havent run into issues so far, then you are provably mitigating the pressure somehow/somewhere
-i personally dont like doing it, because i rather have fresh strings, 1
-i dont like sagging/moving strings, after just replacing 1 or the other, 2
-but finally, it also takes me longer time to just change out 1/2 the racquet, than it does to replace mains and crosses, 3